1. Field of the Invention
The present invention relates to silver halide photographic emulsions spectrally sensitized with novel merocyanine dyes and particularly to silver halide photographic emulsions having high blue sensitivity and high green sensitivity.
2. Description of the Prior Art
It is known that many kinds of cyanine dyes and merocyanine dyes can be used for spectral sensitization of silver halide photographic emulsions.
However, although many types of merocyanine dyes have been studied and developed hitherto, their sensitization is not yet sufficient from a practical standpoint. Although some merocyanine dyes have a quite excellent sensitization, they easily generate fog and the sensitivity of the photosensitive material remarkably decreases during the storage thereof. Further, the merocyanine dyes remaining in the silver halide layers after development stain the resulting images. Thus, it is desired in the photographic field to solve these technical problems.